Apparatuses such as a tape recorder, etc., which utilize magnetic tapes as memory medium, are more and more widely used. However, they had a drawback to have often trouble that a tape twines or winds up round a capstan, etc. while it is forwarded. Mechanical measures are taken to rotate reversely the rewinding reel so that the tape is not broken, when such a twine of the tape is produced, but the twine of the tape itself is not stopped.
In order to remove such a drawback, heretofore various sorts of twine preventing devices have been developed. However, all the prior art devices had drawbacks that they are large from the mechanical point of view, which causes a problem on the space for mounting them, and in addition their cost is high.